Method for developing films



Feb. 22, 1966 Filed April 14, 1965 W. LIMBERGER METHOD FOR DEVELOPINGFILMS 3 Sheets-Sheet 1 Feb. 22, 1966 w. LIMBERGER METHOD FOR DEVELOPINGFILMS 5 Sheets-Sheet 2 Filed April 14, 1965 Feb 22, 1966 W. LIMEERGER3,233,559

METHOD FOR DEVELOPING FILMS Filed April 14, 1.965 5 Sheets-Sheet 3 W A fA United States Patent 3,236,650 METHOD FOR DEVELOPING FILMS WalterLimberger, 248 Alte Landstrasse, Hamburg-Poppenbuttel, Germany FiledApr. 14, 1365, Ser. No. 452,440 12 Claims. (CI. 9650) This applicationis a continuation-in-part of my patent application Serial No. 221,809,filed September 6, 1962, now abandoned.

The invention relates to a method of treating exposed photographicemulsions on a layer carrier. In particular, the invention relates tothe developing of photographic silver halide emulsions.

Known surface developing methods operate with developer liquid whichmust be specially prepared and renewed from time to time. In time, thequality of the liquid deteriorates, e.g. by oxidation, so that besidesthe disadvantages which arise from the use of a developer liquid varyingdevelopment results are obtained with increasing age of the developer.

It is further known to arrange the halogen silver emulsion layer,together with the layer wit-h the developer material, on a paperbacking. One disadvantage of this arrangement lies in the limitation ofthe storage period of the paper, which furthermore must be stored undercomparatively constant conditions in order to avoid a premature startingof the effect. For long storage periods, however, reactions can occurunder normal conditions which impair the usefulness of the film.

The main object of the invention is to provide a method of the kindindicated which comprises the steps of forming a solid member from afusion material combined with a treatment medium selected from the groupconsisting of developers, developer forming materials, and fixingmaterials, causing a surface layer of said member to dissolve, andmoving said member and layer carrier relative to each other with saiddissolved surface layer of the member in contact with said photographicemulsion.

Another object of the invention is to carry out said step of causing asurface layer of the member to dissolve by applying heat to said member.

A further object of the invention is carry out said step of causing asurface layer of the member to dissolve by applying a solvent to saidmember.

Other objects and advantages of the invention will become evident fromthe following description thereof with reference to the accompanyingdrawings, in which:

FIG. 1 is a vertical section of an embodiment of an apparatus suitablefor practicing the invention,

FIG. 2 is a section on line II-II of FIG. 1,

FIG. 3 is a section on line IIIIII of FIG. 1,

FIG. 4 is a cross-section of the abovementioned solid member, in thiscase in the form of a roller,

FIG. 5 is a vertical section of a machine suitable for molding the solidmember in the form of a roller,

FIG. 6 is a section of a mold used in the machine of FIG. 5, and

FIG. 7 shows a portion of said mold viewed as indicated by the arrowsVII-VII in FIG. 6.

The apparatus shown in FIGS. 1-3 comprises a housing having a lower part1 and a removable cover 2. The parts within the housing are supported onintermediate walls 3, 4, which if necessary can be arranged in the lowerpart 1 so as to be removable after removal of the cover 2 and release ofthe drive connection with the parts supported thereon.

Between the walls 3 and 4 a chemical roller 5, described in detailbelow, is rotatably supported in the lower part of the housing.

The chemical roller 5 is carried on a shaft the ends 5a., 5b of whichare rotatably supported in bearings 6, 7. The

shaft end 5b extends through the wall 4 and carries a drive Wheel 8.With this drive wheel there engages a pinion 8a on the drive shaft of amotor drive unit 9 which is arranged on the side of the wall 4 facingaway from the wall 3 within the housing 1, 2.

In the walls 3, 4 a drum It) is supported so as to be adjustable inheight and, as can be seen from FIGURES l and 2, has shaft ends 11, 12rotatably mounted in bearing sleeves 13, 14 having two vertical andparallel sides engaging in longitudinal slots 15, 16 in the walls 3, 4.Between the upper limiting edge of the slots 15, 16 and the bearingsleeves 13, 14 there are respectively arranged compression springs 17,18 which are stressed to press the drum 10 downwards onto the roller 5.The lower ends of these springs are supported on shoulders on thesleeves 13, 14, adjustable countersupports being provided for the upperends of these springs. In view of the driven operation of the roller 5the slots 15, 16 must extend downwards sufiiciently to enable the drum10 to be rotated by engagement with the roller 5.

The bearing sleeves 13, 14 extend to the outsides of the walls 3, 4,respectively, from the slots 15, 16 and are formed beneath their endswith supporting surfaces for actuating rods of solenoids 19, 20. Thesolenoids are arranged on the walls 3, 4 and serve to lift the drum 10from the roller 5 after stopping of the apparatus. It is possible toarrange the solenoids 19, 20 so that upon stopping of the apparatus theyare automatically actuated. Furthermore, it is possible to latch thelifting rods in the raised position by means of special latchingmechanisms (not shown) so that the solenoids can be de-energized afterraising of the drum 10, the latching parts being releasable by specialelectromagnets (not shown) when the apparatus is again operated.

The drum 10 is a heating drum having a peripheral surface of good heatconducting material, if required with a covering of plastics material,which is preferred to other substances. Heater elements 102 aresupported within the drum, for example on its end walls. The elec tricalconnection to the heater elements is effected through the hollow ends 12by flexible conductors 21 which lead to a power supply unit 22.

It is to be noted that an arrangement of the chemical rollers above theheating drum also lies Within the scope of the invention, whereby theheat rising within the apparatus is used particularly advantageously.From FIG. 3 it can be seen that at the level of the nip between the drum10 and the roller 5 slots 23, 23' are arranged in the side walls of theapparatus for the introduction and discharge of films. Between theseslots and the drum guide elements 24, 25 and 26, 27 are provided forguiding films to the nip between the roller and the drum.

There is suitably arranged beneath the chemical roller 5 a collectingcontainer 29, removable through an opening 28 in the housing, whichreceives any downwardly falling dust.

It is possible to arrange special strips at the inner ends of the guideelements 24 to 27 extending the length of the drum or the roller inorder to ensure a safe guiding of the films. In particular, the drum 10can be constructed with peripheral grooves in which fingers of the guideelements 24 engage at the outlet side.

In the illustrated embodiment only the roller 5 is driven, while thedrum 10 is rotated by engagement with the roller 5. In this way, thereis obtained a relative speed which causes a friction effect between theroller 5 and any film passing through. This friction provides transferof the substances contained in the chemical roller to the emulsion layeron the film. Suitably, there is provided an adjustable braking of thedrum 10 by means of an elastic braking element which can be pressedagainst the drum and which is indicated in FIGURE 1 by reference numeral30. By means of this braking element the relative speed or the frictioneffect can be adjusted. An actuating lever 31 for this braking elementextends sideways through a slit in the housing, as shown in FIGURES 2and 3 and can be locked in various positions by known means (not shown).

Other embodiments of the apparatus are shown in the abovementionedparent application.

The roller 5 may be produced in any suitable way. In the machine ofFIGS. 5-7 a mold is used for the purpose. As indicated in FIG. 7, thismold is designed for producing two identical rollers 5 simultaneously,only part of the mold being shown in said FIG. 7.

As viewed in FIGS. 6 and 7, the mold 40 is split on a horizontal planeincluding the broken line connecting the arrows VII-VII. The lower moldportion 41 and the upper mold portion 42 are provided with accuratelyaligned vertical bushings 43 in which guide rods 44 are received with asnug fit to ensure accurate alignment of the two mold portions 41, 42.To the top of the upper mold portion 42 a horizontal press plate 45 isremovably secured by any suitable means (not shown). The lower moldportion 41 is provided with depending legs 46, 47 (see also FIG. 5) attwo opposite sides thereof, and another horizontal press plate 48 issecured to the bottom ends of said legs 46, 47. Centering discs 49, 50are disposed in central recesses 51 and 52, respectively, in the outersides of the press plates 45, 48 and project from said recesses for apurpose explained below.

In the surfaces facing each other the mold portions 41, 42 are eachprovided with a recess 53 and 54, respectively, ada ted to receive lowerand upper mold inserts 55 and 56, respectively, which are removablysecured in place by means of bolts 57, 58 which are accessible from theoutside of the mold portions 41, 42 after removal of the press plates48, 45. The inserts 55, 56 are provided with a lining 59, 60 of Teflonor a similar material on their inner surfaces which together define acylindrical cavity corresponding to the chemical roller 5 to beproduced.

In the embodiment shown the mold 40 is designed for simultaneous moldingof two rollers 5 (only one shown) and in the space between the twocorresponding recesses the mold portions 41, 42 are provided withregistering ingot grooves, the groove 61 in the top surface of the lowermold 41 being shown in FIG. 7. Connecting grooves 62 providecommunication between said ingot grooves 61 and the cavities for therollers 5 in the mold. From the ingot grooves a nozzle 62 extendsupwardly through the mold portion 42 and upper press plate 45 to providecommunication with an opening 63 in the center of the upper centeringdisc 49.

A holding plate 64 for an ejector assembly, generally marked 65, isdisposed on top of the lower press plate 48. The ejector assembly 65comprises an ejector plate 66 provided with upwardly extending ejectorpins 67 and 68. The ejector pin 67 extends through the lower moldportion 41 into abutment with the lower surface of the upper moldportion 42 in the center thereof, while the ejector pins 68 extendthrough the lower mold portion 41 to the periphery of recesses in themold portions adapted to receive the projecting shaft ends 5a, 5b of theroller 5, as will be further described below. An ejector rod 69 extendsthrough aligned central openings 70, 71 in the lower press plate 48 andthe lower centering disc 50, respectively, into engagement with thebottom end of the ejector pin 67. A compression spring (FIG. 5)surrounds the ejector bar 69 and is so arranged as to urge the ejectorassembly 65 and holding plate 64 against the lower press plate 48.Holding springs 72 are secured to the lower mold portion 41 in positionto urge centering pins 73 secured thereto into engagement with the shaftends 511, 5b.

It is to be understood that in the above description of the mold termssuch as horizontal, vertical, upper, lower, top, bottom, etc., have beenused only for convenience in describing the arrangement, and that inactual use the mold may be placed in positions where said terms nolonger apply. Thus, in the machine shown in FIG. 5, the mold occupies aposition in which, e.g., the press plates 45, 48 are vertical ratherthan horizontal, etc. The molding machine shown in FIG. 5 is ofconventional type and will be only briefly described.

The molding machine comprises a holding disc and a holding disc 81provided with a horizontal shaft 82 which by conventional means (notshown) is reciprocable on a horizontal axis towards and from the holdingdisc 80, as indicated by the arrows 83. The mold 40 is held between saiddiscs 80, 81 With the projecting portions of the centering discs 49, 50received in corresponding recesses 84, 85 in the holding discs 80 and81, respectively. The holding discs 80, 81 are provided with centralopenings registering with the openings 63, 71 in the centering discs 49,50, as shown. A horizontal nozzle 86 extends into engagement with thenozzle 62 in the mold and is secured to a cylinder 87 in which a feedscrew 88 is rotatably mounted and connected with gear means 89, 90connected with a drive means (not shown). Bearings 91, 92 are providedfor the feed screw 88 and an axle 93 carrying the gear 90, respectively.The outlet end of a feed funnel 94 is in communication with the interiorof the cylinder 87 at a point remote from the holding disc 80 and has astirring device 95 connected with a drive motor 96. A slide valve 97 ismounted at the outlet end of the funnel 94 and operably connected withthe movable holding disc 81 through a linkage system showndiagrammatically at 98. Heating bands 99 are provided on the outsides ofthe funnel 94, the cylinder 87 and the nozzle 86, as shown.

A preferred embodiment of a roller according to the invention is shownin cross-section in FIG. 4. It comprises a shaft 100 having the endportions 5a, 5b. T0 the shaft is secured a longitudinally corrugatedmetal cylinder 101 to the circumferance of which the chemical material103 described below is applied. In another preferred embodiment the endportions 5a, 5b of the shaft are integral with said shaft and of thesame diameter as indicated in broken lines in FIGS. 6 and 7. Thecylinder 101 may then be omitted and the chemical material is applieddirectly to the shaft.

A suitable material for a developer roller is obtained, e.g., by mixingone part by weight of sodium carbonate (Na CO with two parts by weightof crystallized sodium tetraborate (Na B O -HOH O) during continuousstirring and heating to about F. For special purposes small amounts ofother ingredients, such as alum or methylumbelliferone, may be added,with effects which are known in the art. The mixing and heating may takeplace in the funnel 94 or before introduction thereinto.

Another example of a suitable material for the roller is a mixture ofsodium carbonate and crystallized sodium tetraborate in the proportionsset forth and with the addition of one-half part by weight ofcrystallized sodium acetate (CH COONa-3H O). This addition improves thecontrast characteristics of the images and also renders the roller lesssensitive to temperature fluctuations.

When a pair of rollers 5 are to be molded in the machine, the moldportions 41, 42 are separaed without relative movement between the moldportion 41 and the ejector assembly 65. The roller shafts, which arepreferably made of a corrosion resistant metal, are then placed in themold with the shaft ends 5a, 5b in proper positions between the springs72 and the mold is closed whereby the valve 97 is opened through theintermediary of the linkage 98 and the drive means for the feed screw 88is started. Thereby mixture from the funnel 94 is pressed by the feedscrew 88 through the nozzles 86 and 62 into the grooves 61, 62 and thecavities in the insert aggregate S5, 56 until said spaces are filled anda pressure on the order of 500 atm. has been reached. The feeding ininterrupted and the material in the mold 40 is left to cool. The moldportions are then again separated and the ejector assembly is actuatedagainst the action of the spring 75 to free the shaft ends 5a, 5b fromthe springs 72 and thus permit removal of the rollers 5. The ejectorpins are retracted, a pair of new shafts are inserted, the mold isclosed and the procedure is repeated.

The relative velocity of the roller 5 and the layer carrier to bedeveloped in the machine of FIG. 1 is dependent to a certain extent uponwhether the heat supply to the press roller is intermittent or constant,and if liquid is used to dissolve the surface of the roller 5, theamount of liquid supplied also has a bearing upon said relativevelocity. Generally speaking, it is of the order of about 1:3. In caseof heat supply, the temperature should be above about 140 F. It shouldbe noted that the supply of heat instead of through the interior heatingmeans 102 may be effected by heat radiation from the outside.

The pressure of the roller 10 against the roller 5 need only besufiicient to achieve the desired movement of the layer carrier. Itsactual value is dependent upon the degree of softness of the surfacelayer of the roller 5 caused by the heat or liquid used, and it isreadily controllable on the basis of visual observation during the firstmoments of operation.

It is, of course not necessary that the chemical member be in the shapeof a roller. It may have the shape of a block or a plate, the essentialcondition being the relative movement between the chemical member andthe layer carrier. In the last mentioned case the manufacturingprocedure will be similar to that described above, although the interiorshape of the mold inserts will be different.

What I claim is:

1. A method of treating exposed photographic emulsions on a layercarrier, comprising the steps of forming a solid member from a fusionmaterial combined with a treatment medium selected from the groupconsisting of developers, developer forming materials, and fixingmaterials, causing a surface layer of said member to dissolve, andmoving said member and layer carrier relative to each other with saiddissolved surface layer of the member in contact with said photographicemulsion.

2. A method of treating exposed photographic emulsions on a layercarrier, comprising the steps of forming a solid member from a fusionmaterial combined with a treatment medium selected from the groupconsisting of developers, developer forming materials, and fixingmaterials, applying heat to said member so as to cause a surface layerthereof to dissolve, and moving said mem ber and layer carrier relativeto each other with said dissolved surface layer of the member in contactwith said photographic emulsion.

3. A method of treating exposed photographic emulsions on a layercarrier, comprising the steps of forming a solid member from a fusionmaterial combined with a treatment medium selected from the groupconsisting of developers, developer forming materials, and fixingmaterials, applying solvent to said member so as to cause a surfacelayer thereof to dissolve, and moving said member and layer carrierrelative to each other with said dissolved surface layer of the memberin contact with said photographic emulsion.

4. The method as set forth in claim 1, in which said relative movementbetween the member and the layer carrier is effected so as to causepressure and a rubbing action between said surface layer of the memberand said photographic emulsion.

5. The method as set forth in claim 1, including incorporating in saidfusion material a substance which upon solidification forms a protectivecoating upon said photographic emulsion.

6. The method as set forth in claim 1, including the use of a fusionmaterial containing water or crystallization.

7. The method as set forth in claim 1, including the use of a fusionmaterial containing borax and soda.

8. The method as set forth in claim 1, including the use of a fusionmaterial containing alkali.

9. The method as set forth in claim 1, including the use of a fusionmaterial containing thiosulfate.

10. The method as set forth in claim 5, including the use of a fusionmaterial containing alum.

11. The method as set forth in claim 5, including the use of a fusionmaterial containing methylumbelliferone.

12. A method of treating exposed photographic emulsions provided onlayer carriers, comprising moving a first member formed from a treatmentmedium containing a developer bound in a dissoluble material over saidemulsion in contact therewith while causing said dissoluble material tobe dissolved so that said developer is transferred to said emulsion, andmoving a second member formed from a treatment medium containing fixersubstances bound in a dissoluble material over said emulsion in contacttherewith while causing said dissoluble material to be dissolved so thatsaid fixer substances are applied to said emulsion.

References Cited by the Examiner UNITED STATES PATENTS 935,115 9/1909Kelly et al. 9666 2,095,836 10/1937 Russell 9666 2,196,901 4/1940 Ham96--66 2,682,464 6/1954 Wiitala et al. 9666 2,739,894 3/1956 Rasch etal. 96--66 3,142,241 7/1964 Limberger 96-51 X NORMAN G. TORCHIN, PrimaryExaminer.

J. CANNON, Assistant Examiner.

1. A METHOD OF TREATING EXPOSED PHOTOGRPAHIC EMULSIONS ON A LAYERCARRIER, COMPRISING THE STEPS OF FORMING A SOLID MEMBER FROM A FUSIONMATERIAL COMBINED WITH A TREATMENT MEDIUM SELECTED FROM THE GROUPCONSISTING OF DEVELOPERS, DEVELOPER FORMING MATERIALS, AND FIXINGMATERIALS, CAUSING A SURFACE LAYER OF SAID MEMBER TO DISSOLVE, ANDMOVING SAID MEMBER AND LAYER CARRIER RELATIVE TO EACH OTHER WITH SAIDDISSOLVED SURFACE LAYER OF THE MEMBER IN CONTACT WITH SAID PHOTOGRAPHICEMULSION.